The invention discloses a PMSM sensorless control strategy based on improved ADRC and high-frequency
square wave injection. The strategy comprises steps that continuous high-frequency
square wave voltage signals are injected into a d axis of a
vector control synchronous rotating coordinate
system of a
permanent magnet synchronous motor, and the frequency of the high-frequency
square wave voltage signals is made to be equal to the
switching frequency of an
inverter; in a single high-frequency
signal injection period, through two times of current sampling, the separation
processing process of the fundamental current and the high-
frequency response current is simplified, and no filter is needed; the fundamental current is used for performing current feedback in
vector control, the high-frequency current comprises the rotor position information, the
position error information is decoupled by adopting the alpha-beta axis high-
frequency response signal cross multiplication method, and the rotor position is observed through a Luenberger
position tracking observer; in terms of a speed controller, an improved linear active disturbance rejection controller is utilized instead of a PI controller. The method is advantaged in that the bandwidth of a sensorless
control system can be improved, and higher dynamic response speed and anti-disturbance performance are achieved.